Unavoidable subprojections in union-closed set systems of infinite breadth
نویسندگان
چکیده
We consider union-closed set systems with infinite breadth, focusing on three particular configurations ${\mathcal T}_{\rm max}(E)$, min}(E)$ and ort}(E)$. show that these are not isolated examples; in any given system of at least one will occur as a subprojection. This characterizes those which have is the first general structural result for such systems.
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2021
ISSN: ['1095-9971', '0195-6698']
DOI: https://doi.org/10.1016/j.ejc.2021.103311